1. The Field of the Invention
The present invention is in the field of fire retardant and heat resistant yarns and fabrics, and other fibrous blends. More particularly, the present invention is in the field of yarns or fabrics that include metallic and/or other high strength filaments, oxidized polyacrylonitrile fibers and, optionally, one or more strengthening fibers.
2. The Relevant Technology
Fire retardant clothing is widely used to protect persons who are exposed to fire, particularly suddenly occurring and fast burning conflagrations. These include persons in diverse fields, such as race car drivers, military personnel and fire fighters, each of which may be exposed to deadly fires and extremely dangerous incendiary conditions without notice. For such persons, the primary line of defense against severe burns and even death is the protective clothing worn over some or all of the body.
Even though fire retardant clothing presently exists, such clothing is not always adequate to compensate for the risk of severe burns, or even death. Due to the limitations in flame retardance and heat resistance of present state of the art of flame retardant fabrics, numerous layers are typically worn, often comprising different fibrous compositions to impart a variety of different properties for each layer.
In view of the foregoing, there has been a long-felt need to find improved yarns, fabrics and other fibrous blends having better fire-retardant properties, higher heat resistance, lower heat transference, improved durability when exposed to constant heat or bursts of high heat, together with adequate strength and abrasion resistance, improved softness, better breatheability, improved moisture regain, increased flexibility and comfort, and other performance criteria. Examples of improved yarns, fabrics and other fibrous blends are disclosed in U.S. Pat. Nos. 6,287,686 and 6,358,608 to Huang et al., and U.S. Pat. No. 4,865,906 to Smith, Jr.
Even though the Huang et al. and Smith patents disclose fire retardant yarns, fabrics and other blends having a high Limiting Oxygen Index (“LOI”) and Thermal Protective Performance (“TPP”), additional strength and cut resistance may be necessary for certain applications, such as in the manufacture of gloves, clothing and other articles of manufacture that require high tensile strength, cut resistance and durability. Thus, it would be a further advancement in the art to provide yarns, fabrics and other heat resistant, fire retardant blends such as those disclosed in Huang et al., but which had greatly increased tensile strength, cut resistance, and even higher abrasion resistance and durability.
Such fire retardant yarns, fabrics, and other fibrous blends are disclosed and claimed herein.